Exploring Adherence Monitoring in Sickle Cell Disease


1 United States site


12 to 17 Years

Study type






About the study

Despite the well-documented benefits of hydroxyurea (HU) therapy in decreasing morbidity and
mortality in youth with Sickle cell disease (SCD), pediatric HU adherence rates range as low
as 49% and lead to discontinuation of HU regimens in 8-20%. In addition, treatment
non-adherence may lead to unnecessary increases in medication dosage resulting from erroneous
assumption that a patient is non-responsive to treatment (versus non-adherent to the regimen
as prescribed). Given the detrimental effects of non-adherence, assessment of and
intervention for HU non-adherence is essential to improving health outcomes in the pediatric
SCD population.

Electronic adherence monitoring is widely considered the “gold standard” in objective
adherence measurement. These monitors provide continuous, real- time records of medication
adherence and reveal problematic behavior patterns, including underdosing, overdosing,
delayed dosing, “drug holidays,” and “white coat” adherence. Overall, electronic adherence
measures are considered valid, reliable, and accurate, with clear advantages over pharmacy
refill records, physician estimates and self-report measures.

The primary purpose of this pilot study is to determine the use of the AdhereTech as a
feasible and valid measure of HU adherence in pediatric SCD.

Primary Objective Estimate the association between HU adherence as measured by the AdhereTech
device to a) caregiver-report, b) youth-report, c) lab values, d) pill- count, and e)
Medication Possession Ratio (MPR) adherence measures Secondary Objectives Estimate the rate
of consent to the study, the rate of AdhereTech device use, the rate of AdhereTech device
failure, and the perceived acceptability of using the AdhereTech device, as reported by
caregivers and youth

participation requirements

– Confirmed diagnosis of SCD (any genotype)

– Ages 12.0 – 17.99 at time of study enrollment

– Stable HU dose composed of only one capsule strength prescribed in pill formulation
for ≥ 6 months without documented hematological toxicity (excluding dose adjustments
for weight gain)

– Lives with their legal guardian

– Anticipated to return to clinic at proposed 4-week intervals

participation restrictions

– Primary caregiver and/or youth unable to understand English and/or youth not
cognitively intact (known IQ < 70) such that the study questionnaire cannot be understood and completed. - Participant unable to complete the questionnaires due to refusal or current acute illness (e.g., pain crisis). - Inability or unwillingness of research participant or legal guardian/representative to give written informed consent.


  • Memphis, Tennessee, United States, St. Jude Children's Research Hospital, 38105